In general, a power for operating electronic products used in home is provided from a power plant operated by public enterprises or private enterprises, through a transmission line, and a distribution line.
However, the above power has the nature of a central power source and not a distributed power source, has a radial-type shape that spreads from the center to the periphery, and is one-directional supplier-oriented and not consumer-oriented.
Due to this, only limited price information on electricity used is provided to a home, i.e., a consumer through a power exchange. Also, since a price system is actually a fixed-price system, there are limitations in selecting electricity at a price that consumers want.
In order to resolve the limitations and improve the efficiency of energy use, studies on a smart grid have been actively in progress in recent years.
The smart grid grafts information technology (IT) on a typical power grid to exchange real-time information in two way communication between a power supplier and a consumer. That is, the smart grid refers to a next generation power system and its management system for optimizing energy efficiency.
Moreover, in order to implement the above smart grid at home, the need on two-way communication relating to power supply source and power information, being free from the case that an individual electronic device unilaterally receives power from a network having a plurality of electronic devices connected, and also, the need on new devices for the two-way communication are being considered.